Currently, polyarylene sulfide is representative engineering plastic, and is in great demand for high temperature and corrosive environment and electronic products due to high heat resistance, chemical resistance, flame resistance, and electric insulation. The major uses include computer accessories, automobile accessories, coating of the part contacting corrosive chemical materials, and industrial chemical resistant fiber, and the like.
Presently, polyphenylene sulfide (PPS) is the only commercially available polyarylene sulfide. According to the current commercial production process of PPS, p-dichlorobenzene (pDCB) and sodium sulfide are used as raw materials and reacted in a polar organic solvent such as N-methyl pyrrolidone, and the like. This method is known as a Macallum process, and the basic process is disclosed in U.S. Pat. Nos. 2,513,188 and 2,583,941, wherein some usable polar solvents are suggested, but N-methylpyrrolidone is currently most commonly used. This process uses dichloro aromatic compounds as raw material, and sodium chloride (NaCl) is generated as a by-product.
Meanwhile, since PPS obtained in the Macallum process generally has good flowability at high temperature, it may be molded even under low pressure and has good processability. However, if products requiring high accuracy or having flat shapes such as various computer accessories or electronic products are manufactured, flash or burr may be generated in the molded product, and thus, this process has a limitation in the manufacture of precision parts. In addition, since molding should be conducted at high temperature in order to apply for precision parts and improve flowability, a large amount of the generated outgas may injure operator's health, and it may cause air pollution.